A 4-week repeated oral dose toxicity study of the methanol extract from Diospyros canaliculata in rats

We studied the toxic effects of the methanol extract from the stem bark of Diospyros canaliculata via oral administration in rats. Extract was tested in an oral 28-day study at doses of 0.5, 1 and 2 g/kg body weight (bw). Toxicological endpoints examined included blood cell counts and selected organ weights, histopathological examination of the liver and kidneys tissue and biochemical parameters including alkaline phosphatase (ALP), aspartate aminotransaminase (AST) and alanine aminotransaminase (ALT). The extract significantly increased concentrations of serum ALP, AST, total protein and urea at 2 g/kg bw. A significant increase (p < 0.05) was also noted in ASAT activity in 20% liver homogenate of rats receiving the highest dose. Results suggest that the methanol extract from the stem bark of D. canaliculata is slightly toxic, and therefore, has a low margin of drug safety. Long-term studies are required in order to rule out any long-term adverse effects.